Trailing by 13 points in the fourth quarter, the Warriors rallied and had a chance to tie it in the waning seconds, The Associated Press reported.
Stephen Curry drove down the lane and passed to big man Damian Jones, who had his shot blocked from behind by Hernangomez.
The Nuggets improved to 3-0 despite missing 18 free throws, including six in the final quarter.
Nikola Jokic had 23 points, 11 rebounds and six assist in his bid for a triple-double on a second straight night.
The 3-0 start is Denver's best since the 2009-10 squad led by Carmelo Anthony and Chauncey Billups began 5-0. This victory was driven by defense. Denver was sluggish in the second game of a back-to-back but turned up the defensive intensity. The Nuggets forced 18 turnovers.
No surprise, Curry hit three straight three-pointers in a 1:11 span to lead the comeback. He finished with 30 points and had six three-pointers to move him past Paul Pierce for sixth place on the NBA's career list.
Draymond Green had a chance to tie the game at 99-all with 9.6 seconds remaining, but his second free throw rolled out. Jamal Murray made one of two free throws on the other end to make it 100-98 and set the stage for Hernangomez.
Brandon Ingram, Rajon Rondo and Chris Paul were suspended by the NBA after a punch-up during the Los Angeles Lakers' defeat by the Houston Rockets.
Lakers duo Ingram and Rondo have been banned for four and three games respectively, while the Rockets' Paul has a two-game ban – all without pay, BBC Sport reported.
Paul said Rondo spat in his face, which led to the fracas that Lakers star LeBron James helped break up.
An NBA statement said all three had thrown punches.
"Ingram has been suspended for aggressively returning to and escalating the altercation and throwing a punch in the direction of Paul, confronting a game official in a hostile manner, and instigating the overall incident by shoving Rockets guard James Harden," said the statement.
"Rondo has been suspended for instigating a physical altercation with, and spitting and throwing multiple punches at, Paul.
"Paul has been suspended for poking at and making contact with the face of Rondo, and throwing multiple punches at him."
The game was the home debut of three-time NBA champion James and ended with a 124-115 defeat for the Lakers.